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1.
Food Chem ; 455: 139911, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38823129

RESUMO

Ti-metal organic framework (Ti-MOF) doped with carbon dots (CDs) with enhanced antibacterial potential was synthesized using solvothermal-assisted mechanical stirring and used for the fabrication of CMC/Agar-based active packaging films. The incorporation of CD@Ti-MOF not only improved the tensile strength of the CMC/Agar film by 17.4% but also exhibited strong antioxidant activity with 100% of ABTS and 57.8% of DPPH radical scavenging using 0.64 cm2/mL of CMC/Agar/CD@Ti-MOF film. Furthermore, water vapor permeability, oxygen permeability, and ultraviolet light-blocking ability (95.7% of UV-B and 84.7% of UV-A) were improved significantly. The CMC/Agar/CD@Ti-MOF film showed strong antibacterial activity and could inhibit the progress of E. coli up to 8.2 Log CFU/mL and completely stopped the growth of L.monocytogenes after 12 h of incubation. Additionally, CMC/Agar/CD@Ti-MOF film extended the shelf life of cherry tomatoes preserved at 4 °C and delayed the quality degradation, maintaining the visual aspects of the packaging.

2.
Food Res Int ; 188: 114467, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823836

RESUMO

Cellulose-based packaging has received great attention due to its characteristics of biodegradability, sustainability, and recyclability. Natural polymer coatings are usually applied to the paper surface to enhance the barriers to water vapour and improve the mechanical properties. A chitosan-based coating for paper packaging was developed in this work to store specialty roasted coffee beans, evaluating two samples of chitosan (Sigma® and molasses chitosan), and following the physico-chemical and microbiological characteristics of coffee beans along a period of 60 days. Sensory tests (Ranking Descriptive Analysis and Preference Test) were applied to the beverage prepared with the roasted and ground coffee beans stored in each packaging. Thin chitosan films provided good coverage and adhesion on the paper. Improved mechanical properties and lower water permeability were observed in the chitosan-coated papers. The physicochemical and microbiological characteristics of the coffee beans were not influenced by the packaging along 60 days of storage. The molasses chitosan coating resulted in slightly darker roasted beans. In sensory evaluation, there is a clear difference between the chitosan samples, so that molasses chitosan-coated packaging had higher scores compared to Sigma® chitosan treatment for flavor and global impression in the preference analysis of the beverage. The molasses chitosan-coated packaging had three to four more consumers attributing the highest scores for the beverage prepared with the roasted beans stored in this type of packaging.


Assuntos
Quitosana , Embalagem de Alimentos , Papel , Quitosana/química , Embalagem de Alimentos/métodos , Café/química , Bebidas/análise , Sementes/química , Sementes/microbiologia , Humanos , Paladar , Coffea/química , Coffea/microbiologia , Comportamento do Consumidor , Permeabilidade
3.
Food Res Int ; 188: 114475, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823838

RESUMO

This work aimed to develop edible emulsion-based barriers in the form of chitosan composite films, with a focus on assessing the impacts of carnauba wax, rosin resin, and zinc oxide nanoparticles on their properties. Six films were produced by casting using chitosan as polymer base and glycerol as plasticizer. Acetic acid and polysorbate 80 were also used to facilitate the dissolution and mixing of the components. The six filmogenic solutions contained chitosan at 1.2% w/v, wax or resin content with 0 or 0.6% m/v and ZnO with 0 or 0.05% m/v. The dried films were characterized according to their chemical, barrier, mechanical, thermal and optical properties. All treatments resulted in flexible films. Chitosan films appeared smoother and more uniform under SEM imaging, while carnauba wax films displayed roughness due to their hydrophobic nature. Wax and resin films were less transparent and water soluble than the chitosan-only films. On the other hand, the addition of ZnO in the formulations increased the solubility of the films. The sorption degree was in line with the solubility results, i.e., films with ZnO presented higher sorption degree and solubility values. All treatments showed low or non-light UV transmission, indicating that the films provide good barrier to UV light. In the visible light region, films of resin with ZnO showed the lowest transmittance values, hence offering a good barrier to visible light. Among the evaluated films, chitosan, and resin films with ZnO nanoparticles were more rigid and resistant to deformation. Overall, films produced with rosin resin and ZnO nanoparticles showed potential improvements in barrier, mechanical, thermal, and optical properties, mainly due to their low water solubility, good UV protection and low permeability to water vapor and oxygen, which are suitable for using in formulations, intended to produce edible films and coatings.


Assuntos
Quitosana , Nanocompostos , Resinas Vegetais , Solubilidade , Ceras , Óxido de Zinco , Quitosana/química , Óxido de Zinco/química , Nanocompostos/química , Resinas Vegetais/química , Ceras/química , Nanopartículas/química , Embalagem de Alimentos/métodos , Permeabilidade
4.
Heliyon ; 10(10): e31408, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38826753

RESUMO

Nowadays, a wide variety of labels of items are widely available, and human consumption is increasingly tailored to meet their individual needs. So, many businesses are starting to focus on improving the functionality of modern packaging. Sensorial paradigms and emotional reactions could change during the user-product interaction lifecycle. The designer's emotional imagination and past experiences are the backbone of conventional product package design, which has limitations due to unmanageable content and an absence of professional advice-the majority of previous research on emotional image analysis aimed to forecast the most common viewer emotions. Since the feelings a picture evokes are quite individual and vary from viewer to viewer, this overarching feeling isn't always enough for practical uses. The research presented an approach to packaging design evaluation based on image emotion perception computing (PDE-IEPC), which combines emotion perception technology with a deep LSTM (Long short-term model), resulting in an immersive and dynamic experience for the human senses. Emotion Perception Computing's Dynamic Multi-task Hypergraph Learning (DMHL) approach considers graphical data, social context, spatial evolution, and location, among other criteria, to evaluate packaging designs efficiently based on their emotional impact. Image-Emotion-Social-Net is a large dataset used to evaluate multidimensional and categorical attitude representation. The dataset is sourced from Flickr and contains over 1 million images presented by over 9000 users. Personalized emotion categorization is an area where research on this dataset shows that the suggested strategy outperforms many modern techniques. The experimental results show that the proposed method achieves a high packaging design quality rate of 94.1 %, a performance success rate of 97.5 %, and a mean square error rate of 2 % compared to other existing methods.

5.
Meat Sci ; 215: 109548, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38838568

RESUMO

This study aimed to develop an appropriate modified atmosphere packaging (MAP) system for displayed beef steaks following long-term superchilled (-1 °C) storage. After superchilled storage for 0, 2, 8, or 16 weeks, beef loins were fabricated into steaks and displayed with 20%, 50%, or 80% O2-MAP under chilled conditions. At each storage point, after display for 0, 3, 7, or 10 days, instrumental color, myoglobin redox forms percentage, lipid oxidation, total viable count (TVC), and total volatile basic nitrogen (TVB-N) were evaluated. Meat color stability decreased, with prolonged storage period and display time. When the storage period was within 8 weeks, under all the above MAP conditions, the display time for the beef steaks was up to 10 days. Considering 80% O2-MAP promoted lipid oxidation, 50% and 80% O2-MAP were not recommended for displaying steaks for more than 10 and 7 days respectively after 16 weeks of storage. However, 20%, 50%, or 80% O2-MAP could maintain 3 days of microbial shelf-life according to TVC and TVB-N results. Additionally, after long-term superchilled storage for 16 weeks, the various O2 concentrations had minimal impact on microbiota succession during the MAP display period. Furthermore, beef steaks packaged under various MAP systems exhibited similar microbial compositions, with the dominant bacteria alternating between Lactobacillus and Carnobacterium. This study provided practical guidance for improving beef color stability after long-term superchilled storage.

6.
Int J Biol Macromol ; : 132893, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838883

RESUMO

Foodborne pathogens result in a great harm to human, which is an urgent problem to be addressed. Herein, a novel cellulose-based packaging films with excellent anti-bacterial properties under visible light were prepared. A porphyrin-based covalent organic polymer (Por-COPs) was constructed, then covalently grafted onto dialdehyde cellulose (DAC). The addition of Por-COPs enhanced the mechanical, hydrophobicity, and water resistance of the DAC-based composite films. DAC/Por-COP-2.5 film exhibited outstanding properties for the photodynamic inactivation of bacteria under visible light irradiation, delivering inactivation efficiencies of 99.90 % and 99.45 % towards Staphylococcus aureus and Escherichia coli within 20 min. The DAC/Por-COPs films efficiently generated •O2- and 1O2 under visible light, thereby causing oxidative stress to cell membranes for bacterial inactivation. The prepared composite film forms a protective barrier against bacterial contamination. Results guide the development of high performance and more sustainable packaging films for the food sector.

7.
Crit Rev Biotechnol ; : 1-11, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839596

RESUMO

Additives, such as bisphenol A (BPA) that are added to packaging material to enhance functionality may migrate into food products creating a concern for food safety. BPA has been linked to various chronic diseases, such as: diabetes, obesity, prostate cancer, impaired thyroid function, and several other metabolic disorders. To safeguard consumers, BPA migration limits have been defined by regulatory bodies. However, it is important to address the underlying factors and mechanisms so that they can be optimized in order to minimize BPA migration. In this review, we determine the relative importance of the factors, i.e. temperature, contact time, pH, food composition, storage time and temperature, package type, cleaning, and aging, and packaging damage that promote BPA migration in foods. Packaging material seems to be the key source of BPA and the temperature (applied during food production, storage, can sterilization and cleaning processes) was the critical driver influencing BPA migration.

8.
Int J Biol Macromol ; 272(Pt 1): 132816, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38825273

RESUMO

Modulating the interactions between biopolymer matrix and nanofillers highly determined the mechanical performances of composite packaging materials. Herein, we innovatively proposed a sort of eco-friendly and mechanically robust carboxymethyl cellulose/graphene oxide/tannic acid/polyetherimide (CMC/GO/TA/PEI, CGTP) composite by employing PEI as cross-linker and TA as proton donor. The amidation reaction between -NH2 and -COOH chemically connected the CMC/GO, CMC/CMC and GO/GO and the physical interaction (e.g. hydrogen bonds and molecular entanglements) was beneficial to form dense structures. The chemical/physical bonds among polymers and nanofillers contributed to dissipate the external energy. The toughness was effectively reinforced from 1.68 MJ/m3 for CGTP0 to 4.63 MJ/m3 for CGTP1.0. Furthermore, the CGTP1.0 composite film also delivered improved gas (moisture and oxygen) barriers, UV protection and antimicrobial features. Originating from these merits, the shelf life of fresh fruits (e.g. strawberries, blueberries and cherry tomatoes) was prolonged at least 5 days under ambient conditions when the packaging box was covered by the fabricated CGTP1.0 film. Our findings not only provided a facial strategy to reinforce the interactions between biopolymer matrix and nanofillers, but also boosted the development of eco-friendly packaging materials with robust structures in the area of food packaging.

9.
Int J Biol Macromol ; 272(Pt 1): 132509, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38843608

RESUMO

Functional packaging represents a new frontier for research on food packaging materials. In this context, adding antioxidant properties to packaging films is of interest. In this study, poly(butylene adipate-co-terephthalate) (PBAT) and olive leaf extract (OLE) have been melt-compounded to obtain novel biomaterials suitable for applications which would benefit from the antioxidant activity. The effect of cellulose nanocrystals (CNC) on the PBAT/OLE system was investigated, considering the interface interactions between PBAT/OLE and OLE/CNC. The biomaterials' physical and antioxidant properties were characterized. Morphological analysis corroborates the full miscibility between OLE and PBAT and that OLE favours CNC dispersion into the polymer matrix. Tensile tests show a stable plasticizer effect of OLE for a month in line with good interface PBAT/OLE interactions. Simulant food tests indicate a delay of OLE release from the 20 wt% OLE-based materials. Antioxidant activity tests prove the antioxidant effect of OLE depending on the released polyphenols, prolonged in the system at 20 wt% of OLE. Fluorescence spectroscopy demonstrates the nature of the non-covalent PBAT/OLE interphase interactions in π-π stacking bonds. The presence of CNC in the biomaterials leads to strong hydrogen bonding interactions between CNC and OLE, accelerating OLE released from the PBAT matrix.

10.
Int J Biol Macromol ; : 132915, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844289

RESUMO

Non-conventional starch sources have attracted substantial attention due to their preferred physicochemical and mechanical properties similar to conventional sources. This study aimed to enhance the mechanical properties of mango seed kernel starch (MSKS) based films reinforced with carboxymethyl cellulose (CMC) and gum acacia (GA). Physical modification of MSKS was carried out using microwave-assisted at 180 W for 1 min. SEM results confirmed the oval and irregular shape of starch. The particle size of native starch (NS) (754.9 ±â€¯20.4 nm) was higher compared to modified starch (MS) 336.6 ±â€¯88.9 nm with a surface charge of -24.80 ±â€¯3.92 to -34.87 ±â€¯3.92 mV, respectively. Several functional groups including hydroxyl (OH) and carboxyl (CH) were confirmed in NS and MS. Different ratios of the MS, NS, CMC, and GA were used for the fabrication of films. Results revealed the higher tensile strength of M/C/G-1 (57.45 ±â€¯0.05 nm) and M/C/G-2 (50.77 ±â€¯0.58), compared to control C-4 (100 % native starch) (4.82 ±â€¯0.04) respectively. The ternary complex provided excellent permeability against moisture and the film with a higher starch concentration confirmed the uniform thickness (0.09-0.10 mm). Furthermore, selected films (M/C/G-1 and M/C/G-2) reduced the microbial growth and weight loss of the bun compared to the control (C-4) film. Thus, the ternary complex maintained the freshness of the bun-bread for 14 days. It can be potentially used as a cost-effective and eco-friendly packaging material for food applications.

11.
Nutr Bull ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38845598

RESUMO

Research shows that features of food packaging can help to promote healthy food choices. Laboratory-based studies demonstrate that smart design of packaging facilitates portion control. However, the extent to which consumers notice packaging features for portion control is not known. Therefore, this study investigated how individuals interact with food packaging, how they utilise the on-pack serving-size guidelines and how they make portion decisions. To do this, 25 adult participants were recruited to participate in an online semi-structured interview. Data were analysed using thematic analysis until saturation was achieved. Participants reported that they rarely attend to on-pack serving recommendations and indicated some resistance to them. Some structural features (small/single serving, pre-portioned and resealable packaging) were identified as facilitators of portion control. In contrast, the healthiness evaluation of the product from packaging cues was described as a permissive cue to eat more of the product. Participants in this study value their autonomy and control, preferring convenient behavioural choices over recommended portion servings. They also reported future concerns about the effects of their diet on health, but that current context (hunger, convenience) sometimes presented a barrier to healthy eating. Packaging does more than protect its contents, packaging can affect eating decisions to support portion control, and for some, offers permission to overconsume. This study identified ways that participants use packaging to make portion decisions, revealing the role of habits, current context and future health considerations. The interviews revealed the importance of consumer values on food choice in general and portion control in particular. In conclusion, smart food packaging design could use these findings to nudge healthy portion decisions by incorporating consumer values and by recognising consumer needs for habitual, current and future concerns.

12.
Bioresour Bioprocess ; 11(1): 57, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38836876

RESUMO

The canola oil industry generates significant waste as canola meal (CM) which has limited scope and applications. This study demonstrates the possibility of valorization of CM as a sustainable natural filler in a biodegradable polymer composite of Poly(lactic acid) (PLA). Generally, interfacial bonding between natural fibers and the polymer matrix in the composite is weak and non-uniform. One possible solution is to derivatize natural fibre to introduce interfacial bond strength and compatibility with the PLA polymer matrix. Here, CM was succinylated in a reactive extrusion process using succinic anhydride at 30 wt% to get 14% derivatization with 0.02 g of -COOH density per g of CM. The CM or succinylated CM at 5 and 15 wt% was co-extruded with amorphous PLA to get composite fibers. CM-PLA and succinylated CM-PLA biocomposites were foamed using a mild and green microcellular foaming process, with CO2 as an impregnating agent without any addition of organic solvents. The properties of the foams were analyzed using differential scanning calorimetry (DSC), Dynamic mechanical thermal analysis (DMTA), shrinkage, and imaging. The addition of CM or succinylated CM as a natural filler did not significantly change the glass transition temperature, melting point, percent crystallization, stiffness, and thermal stability of PLA foams. This suggests succinylation (modification) of CM is not a mandatory step for improving interphase compatibility with the amorphous PLA. The new PLA-CM foams can be a good alternative in the packaging industry replacing the existing petroleum-based polymer foams.

13.
Int J Biol Macromol ; 272(Pt 1): 132834, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838885

RESUMO

The development of novel packaging materials with antimicrobial properties is crucial in preventing the microbial-induced spoilage of fruits, vegetables, and foodborne illnesses. In this study, homojunction g-C3N4 (HCN) photocatalysts with excellent photocatalytic performance were incorporated into a matrix consisting of pullulan/chitosan (Pul/CS). These photocatalysts were then electrostatically spun onto polylactic acid (PLA) films to fabricate PLA@Pul/CS/HCN nanofibrous composite films. The design of the bilayer films aimed to combine the physical properties of PLA film with the excellent antibacterial properties of nanofiber films, thereby achieving synergistic advantages. The incorporation of the HCN photocatalysts resulted in enhanced hydrophobicity, barrier function, and mechanical properties of the composite films. Under visible light irradiation, the PLA@Pul/CS/HCN films exhibited approximately 3.43 log and 3.11 log reductions of Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA), respectively, within 2 h. The excellent antimicrobial performance could be attributed to the synergistic effect of CS and the release of reactive oxygen species (ROS) from HCN. Moreover, the strawberries packaged in the PLA@Pul/CS/HCN film demonstrated diminished quality degradation and a prolonged shelf life following visible light irradiation treatment. This study will provide new insights into the exploration of safe and efficient antimicrobial food packaging.

14.
Int J Biol Macromol ; 272(Pt 1): 132817, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38834126

RESUMO

Multifunctional smart biopolymeric films were fabricated using rose petal anthocyanin (RPA) and carrageenan (CAR) doped with rose petal-derived carbon dots (RP-CDs). Response surface-optimized RPA showed the highest total anthocyanins and radical scavenging ability. Produced RP-CD exhibited UV absorption and high fluorescence with antibacterial/antioxidant abilities. Enrichment with 2 % RP-CD and 5 % RPA in the CAR matrix results in improved physicochemical, i.e., water contact angle, water vapor permeability, and UV-blocking properties of the fabricated material. Results showed that nanocomposite films scavenged radicals better than the neat CAR films. Zeta potential, FTIR, SEM, and XPS suggested improved compatibility/stability and enhanced elemental configuration of RP-CDs/RPA additives in the CAR polymer matrix. Perishable food packaging (minced pork and shrimp) demonstrated that nanocomposite films work efficiently and non-destructively and are promising tools for monitoring real-time freshness through interpretable visual changes from red to yellow. The CAR/RP-CDs/RPA-based nanocomposite indicator films are expected to be applied as various smart packaging materials. These films possess the ability to promptly detect changes in quality, preserve the quality, and prolong the shelf life of packaged foods.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38728548

RESUMO

Food contact materials (FCMs) from three countries were analysed for all extractable organofluorines (EOFs) from the materials and subsequently by target and non-target analysis for per- and polyfluoroalkyl substances (PFAS). The EOF varied by two orders of magnitude for FCM from UK and Saudi Arabia ranging between 2.14 and 483 ng cm-2 (0.2-48 ng g-1) showing that one quarter of all samples were above the Danish regulation for PFAS in FCM. Target PFAS showed high variability in composition and accounted for less than 1% of the EOF. Non-target PFAS screening using HPLC-ICP-MS and coupled simultaneously to HRMS showed the occurrence of organofluorines which were identified by neither LC-MS/MS nor LC-HRMS. This illustrates that the current target PFAS approaches fail to identify EOFs from FCM, which would be a problem with the new EU proposal to ban all PFAS.

16.
Heliyon ; 10(9): e30338, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38720712

RESUMO

This study developed and evaluated camel bone gelatin films (CBGFs) with glycerol or sorbitol as plasticizers. Gelatin extracted from the bones of camels (Camelus dromedarius) at ages ranging from 2.5 to 7 years was used. A comprehensive analysis was conducted, evaluating a range of properties including thickness, moisture sorption capacity, water vapor permeability (WVP), infrared spectral characteristics, light absorption behavior, solubility, as well as mechanical and thermal attributes. This thorough examination allowed for a nuanced understanding of the diverse characteristics exhibited by the camel gelatin samples across different age groups. The results indicated that camel age, glycerol, and sorbitol had a significant impact on the properties of the film (P < 0.05). Tensile strength ranged from 0.32 MPa to 3.99 MPa, while the percentage of elongation at break varied from 89.42 % to 2.68 %. Film color (lightness, L) ranged from 21.39 to 41.33. Glycerol and sorbitol plasticized films were 100 % water soluble. Moisture sorption increased with temperature (25 °C, 35 °C, and 45 °C), with sorbitol films retaining less water. WVP was low in films from old camel bones and high in glycerol-plasticized CBGF-2.5Y and CBGF-4.5Y. Thermal analysis showed a melting temperature between 158.60 °C and 174.10 °C, depending on bone age and plasticizer. These films demonstrate promise for use in food packaging, coatings, and pharmaceutical applications.

17.
Front Plant Sci ; 15: 1372638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38689845

RESUMO

Introduction: Traditional modified atmosphere packaging (MAP) cannot meet the preservation requirements of winter jujube, and the high respiration rate characteristics of winter jujube will produce an atmosphere component with high CO2 concentration in traditional MAP. Micro-perforated MAP is suitable for the preservation of winter jujube due to its high permeability, which can effectively remove excess CO2 and supply O2. In this study, a microporous film preservation system that can be quickly applied to winter jujube was developed, namely PMP-MAP (precise micro-perforated modified atmosphere packaging). An experiment was designed to store winter jujube in PMP-MAP at 20°C and 2°C, respectively. The quality, aroma and antioxidant capacity, etc. of winter jujube at the storage time were determined. Methods: In this study, the optimal micropore area required for microporous film packaging at different temperatures is first determined. To ensure the best perforation effect, the effects of various factors on perforation efficiency were studied. The gas composition within the package was predicted using the gas prediction equation to ensure that the gas composition of the perforated package achieved the desired target. Finally, storage experiments were designed to determine the quality index of winter jujube, including firmness, total soluble solids, titratable acid, reddening, and decay incidence. In addition, sensory evaluation, aroma and antioxidant capacity were also determined. Finally, the preservation effect of PMP-MAP for winter jujube was evaluated by combining the above indicators. Results and discussion: At the end of storage, PMP-MAP reduced the respiration rate of winter jujube, which contributed to the preservation of high total soluble solids and titratable acid levels, and delayed the reddening and decay rate of winter jujube. In addition, PMP-MAP maintained the antioxidant capacity and flavor of winter jujube while inhibiting the occurrence of alcoholic fermentation and off-flavors. This can be attributed to the effective gas exchange facilitated by PMP-MAP, thereby preventing anaerobic stress and quality degradation. Therefore, the PMP-MAP approach is an efficient method for the storage of winter jujube.

18.
Small ; : e2400740, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693082

RESUMO

Integrating self-healing capabilities into printed stretchable electronic devices is important for improving performance and extending device life. However, achieving printed self-healing stretchable electronic devices with excellent device-level healing ability and stretchability while maintaining outstanding electrical performance remains challenging. Herein, a series of printed device-level self-healing stretchable electronic devices is achieved by depositing liquid metal/silver fractal dendrites/polystyrene-block-polyisoprene-block-polystyrene (LM/Ag FDs/SIS) conductive inks onto a self-healing thermoplastic polyurethane (TPU) film via screen printing method. Owing to the fluidic properties of the LM and the interfacial hydrogen bonding and disulfide bonds of TPU, the as-obtained stretchable electronic devices maintain good electronic properties under strain and exhibit device-level self-healing properties without external stimulation. Printed self-healing stretchable electrodes possess high electrical conductivity (1.6 × 105 S m-1), excellent electromechanical properties, and dynamic stability, with only a 2.5-fold increase in resistance at 200% strain, even after a complete cut and re-healing treatment. The printed self-healing capacitive stretchable strain sensor shows good linearity (R2 ≈0.9994) in a wide sensing range (0%-200%) and is successfully applied to bio-signal detection. Furthermore, the printed self-healing electronic smart label is designed and can be used for real-time environmental monitoring, which exhibits promising potential for practical application in food preservation packaging.

19.
Mar Biotechnol (NY) ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700616

RESUMO

Environmental pollution is a significant problem due to the improper disposal of plastics and shrimp shells outdoors. Therefore, the synthesis of biodegradable film from waste materials is highly important. The novelty of this research lies in the extraction of protein hydrolysates and chitosan from shrimp shells, as well as the fabrication of biodegradable film from these materials. In this study, the composite films were produced using the solution casting method. Moreover, the combined effect of ultrasound pretreatments (UPT) and natural deep eutectic solvents (NADES) was investigated as extraction media, to determine their potential impact on shrimp waste subcritical water hydrolysis (SWH). Shrimp shells were submitted to UPT in NADES solution, followed by SWH at different temperatures ranging from 150 to 230 °C under 3 MPa for 20 min. Then, the physiochemical properties and bioactivities of the hydrolysates were assessed to determine their suitability for use in biodegradable packaging films. Additionally, the physiochemical properties and bioactivities of the resulting hydrolysates were also analyzed. The highest amount of protein (391.96 ± 0.48 mg BSA/g) was obtained at 190 °C/UPT/NADES, and the average molecular size of the protein molecules was less than 1000 Da with different kinds of peptide. Overall, combined UPT and SWH treatments yielded higher antioxidant activity levels than individual treatments. Finally, the application of composite films was evaluated by wrapping fish samples and assessing their lipid oxidation. The use of higher concentrations of protein hydrolysates significantly delayed changes in the samples, thereby demonstrating the film's applicability.

20.
RNA Biol ; 21(1): 14-30, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38797925

RESUMO

As positive-sense RNA viruses, the genomes of flaviviruses serve as the template for all stages of the viral life cycle, including translation, replication, and infectious particle production. Yet, they encode just 10 proteins, suggesting that the structure and dynamics of the viral RNA itself helps shepherd the viral genome through these stages. Herein, we highlight advances in our understanding of flavivirus RNA structural elements through the lens of their impact on the viral life cycle. We highlight how RNA structures impact translation, the switch from translation to replication, negative- and positive-strand RNA synthesis, and virion assembly. Consequently, we describe three major themes regarding the roles of RNA structure in flavivirus infections: 1) providing a layer of specificity; 2) increasing the functional capacity; and 3) providing a mechanism to support genome compaction. While the interactions described herein are specific to flaviviruses, these themes appear to extend more broadly across RNA viruses.


Assuntos
Flavivirus , Genoma Viral , Conformação de Ácido Nucleico , RNA Viral , Replicação Viral , Flavivirus/genética , Flavivirus/fisiologia , RNA Viral/metabolismo , RNA Viral/química , RNA Viral/genética , Humanos , Infecções por Flavivirus/virologia , Montagem de Vírus , Animais , Biossíntese de Proteínas
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